C-17 delivers 20th anniversary lesson for defence contractors

It was two years late, $1 billion over budget and on probation. The deputy secretary of defense wanted to kill it - some wondered how much the US Air Force wanted to save it.

Meanwhile, the US defence budget was falling. There seemed few more inviting targets for cancellation in 1993 than the Boeing C-17A Globemaster III.

It's rare, but sometimes the most problem-plagued development projects transform into model aircraft programmes - the C-17A is living proof.

On 15 September, the USAF and Boeing will celebrate at Edwards AFB, California, the 20th anniversary of the C-17's first flight - and, by implication, one of the most remarkable turnaround jobs in the history of military aircraft acquisition.

"The miracle was that we stayed with the programme," said Richard Hallion, the USAF's chief historian from 1991-2002. "We would sorely miss the capabilities of the C-17 if we did not have that aircraft. The air force simply couldn't meet our global mobility mission without it."

The story of the C-17's survival is perhaps more relevant today than ever. As a new era of defence spending decline looms, US acquisition programmes that are over budget and behind schedule are at high risk of cancellation.

Earlier this year, US Secretary of Defense Robert Gates placed the Lockheed Martin F-35B on "probation", recalling the lowest and most uncertain moment for the C-17A programme.

The Globemaster III has been a workhorse transport worldwide

If the short take-off and vertical landing variant of the fighter is to survive, it may well need to follow the example of the C-17A.

The Globemaster III's plight in the early 1990s seems far removed from how the programme is viewed today.

It has been a workhorse airlifter in a steady series of conflicts, from Bosnia to Kosovo to Afghanistan to Iraq to Libya.

As the aircraft matures, the C-17A has proven to be cheaper to operate per flight hour than the Lockheed Martin C-130H, according to USAF operational cost statistics obtained by Flightglobal.

The programme has really thrived in the last five years. The USAF wanted to buy 180 C-17As, to replace about 285 smaller Lockheed C-141B Starlifters. But Congress has added funding for 43 more C-17As since 2006, raising the overall fleet to 223.

Meanwhile, seven foreign customers have ordered 35 aircraft over the programme's lifetime, with several countries still in negotiations to buy more.

With no additional orders from the USAF, Boeing is in the process of lowering the C-17A production rate from 15 to 10 airframes per year - while maintaining price levels.

Boeing officials consider that achievement a first among military aviation production programmes.

However, the situation 15 years ago was very different. In addition to schedule delays and cost overruns, there were doubts about the C-17A's basic design and engineering.

The wing had failed at 80% of ultimate load testing, signalling a fundamental error in the McDonnell Douglas design calculations.

Hallion also remembers several near-mishaps in flight testing, including high-impact landings and unrecognised stalls.

"If they weren't careful here they could actually lose a vehicle," Hallion recalled.

In one way, putting the programme on probation helped save it. In December 1993, McDonnell Douglas and the USAF agreed on specific terms. The contractor was aware that meeting its obligations may not be enough to save the programme, but the C-17A had no chance if there was another problem.

The agreement provided enough funding for the USAF to buy 40 C-17As through 1995.

If the programme was still behind schedule and over budget at that time, the C-17A would almost certainly be cancelled.

Although the agreement carried a threat, the "stipulated production rates provided McDonnell Douglas stability so it could turn out a better product", wrote Betty Kennedy, chief historian of the Aeronautical Systems Center, who published a history of the C-17 acquisition programme in 2002.

Another significant change was made at the leadership level. Then Brig Gen Ron Kadish was brought in by the USAF to manage the C-17A contract, while McDonnell Douglas moved Donald Kozlowski from the advanced tactical fighter programme to the C-17A.

It had also become clear by 1995 that the C-17A's basic design was highly capable - if McDonnell Douglas could solve its manufacturing problems.

Hallion noted that the C-17's supercritical wing and winglets were based largely on the work of legendary NASA engineer Richard Whitcomb.